A turbocharger is known to supercharge an internal combustion engine, Air enters the engine through a turbocharger via a compressor, which pressurizes the air. The pressurized air flows to an intake manifold and enters the cylinders of the engine. The compressor is coupled to a turbine, which is driven by exhaust gas from the cylinders. The exhaust gas from the cylinders enters an exhaust manifold and flows into the turbine. The exhaust gas exits the turbine and is vented to the atmosphere. A fraction of the exhaust gas may be diverted from entering the turbine and routed back to the intake manifold. The compressor boosts pressure in the engine air intake system downstream of the compressor. The boost is controlled by controlling turbine operation.
Improper turbocharger control may result in poor engine performance, including stumbling and hesitation, as well as excessive smoke and undesirable hydrocarbon and oxides of nitrogen (NOx) emissions.
Accordingly, there is a need for a turbocharger control system that improves engine performance and reduces undesirable emissions.